﻿Shader "Custom/half_lambert" {
	Properties {
		_diffuse ("diffuse", Color) = (1,1,1,1)
	}
	SubShader {
		pass {
			Tags { "LightMode"="ForwardBase" }
			CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag
			#include "Lighting.cginc"

			fixed4 _diffuse;
			struct a2v {
				float4 vertex : POSITION;
				float3 normal : NORMAL;
			};
			struct v2f {
				float4 pos : SV_POSITION;
				fixed3 worldNormal : NORMAL;
			};

			v2f vert(a2v v){
				v2f o;
				o.pos = UnityObjectToClipPos(v.vertex);	
				o.worldNormal = normalize(mul(v.normal, (float3x3)unity_WorldToObject ));

				return o;
			}

			fixed4 frag(v2f i) : SV_Target {
				fixed3 ambient = UNITY_LIGHTMODEL_AMBIENT.xyz;
				fixed3 worldLight = normalize(_WorldSpaceLightPos0.xyz);
				fixed3 halfLambert = dot(i.worldNormal,worldLight)*0.5+0.5;
				float3 diffuse = _LightColor0.rgb * _diffuse.rgb * halfLambert;

				fixed3 color = ambient + diffuse;
				return fixed4(color,1.0);
			}

			ENDCG
		}
	}
	FallBack "Diffuse"
}
